#include<iostream>
using std::cout; using std::endl; using std::cin;
#include<string>
using std::string;
#include<vector>
using std::vector;
class Transaction {
    public:
        Transaction();
        virtual void logTransaction() const = 0;
    private:
        int amount;
        double prices;
        string type;
};
Transaction::Transaction(){
    logTransaction();
}

// void Transaction::logTransaction() const{
//     cout << "Transaction::logTransaction" << endl;
//     cout << type << endl;   
// }

class BuyTransaction: public Transaction {
    public:
       virtual void logTransaction() const;
};
void BuyTransaction::logTransaction() const{
    cout << "BuyTransaction::logTransaction" << endl;   
}

class SellTransaction : public Transaction{
    public:
        virtual void logTransaction() const;
};
// void SellTransaction::logTransaction() const{
//     cout << "SellTransaction::logTransaction" << endl;   
// }

int main(){
    BuyTransaction b;

}